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United States Patent |
5,269,503
|
Hiroi
,   et al.
|
December 14, 1993
|
Sheet processing apparatus with detachable staple cartridge and
cartridge locking means
Abstract
A sheet post-processing apparatus includes a stapling unit including a
detachable staple cartridge for holding staples attached in series, a
staple driving device for sequentially driving the series of staples into
sheets from a front-end portion, and a staple feeder for feeding the
staples from the staple cartridge to the staple driving device. The sheet
post-processing apparatus further includes a cartridge regulating device
engageable with the staple cartridge for inhibiting detachment of the
staple cartridge as a result of the engagement, a detector for detecting
the presence or absence of the staples, and a releasing device for
disengaging the regulating device when the absence of staples is detected
by the detector to allow removal of the staple cartridge for replacement
of the staples.
Inventors:
|
Hiroi; Masakazu (Yokohama, JP);
Kobayashi; Kenji (Tokyo, JP);
Wakao; Naho (Machida, JP)
|
Assignee:
|
Canon Kabushiki Kaisha (Tokyo, JP)
|
Appl. No.:
|
000566 |
Filed:
|
January 4, 1993 |
Foreign Application Priority Data
Current U.S. Class: |
270/58.09; 227/2 |
Intern'l Class: |
B42B 002/00; B21J 015/28 |
Field of Search: |
270/37,53,58
227/2,156,8
|
References Cited
U.S. Patent Documents
4386725 | Jun., 1983 | Chambers | 227/2.
|
4508329 | Apr., 1985 | Hubler | 227/2.
|
4515356 | May., 1985 | Mullritter | 270/53.
|
4516713 | May., 1985 | Meijer | 227/2.
|
4523750 | Jun., 1985 | Hubler | 270/53.
|
4801133 | Jan., 1989 | Ishiguro et al. | 270/37.
|
4886259 | Dec., 1989 | Ishikawa et al. | 270/53.
|
4978045 | Dec., 1990 | Murakami et al. | 227/120.
|
Foreign Patent Documents |
301596 | Feb., 1989 | EP | 270/53.
|
123763 | May., 1988 | JP | 270/53.
|
2-33207 | Sep., 1990 | JP | 227/2.
|
2-97493 | Dec., 1990 | JP | 270/53.
|
Primary Examiner: Look; Edward K.
Assistant Examiner: Ryznic; John
Attorney, Agent or Firm: Fitzpatrick, Cella, Harper & Scinto
Parent Case Text
This application is a continuation-in-part continuation division, of
application Ser. No. 07/763,456 filed Sep. 20, 1991, now abandoned.
Claims
What is claimed is:
1. A sheet processing apparatus comprising:
a stapling unit comprising:
a detachable staple cartridge for holding staples connected in series;
staple driving mens for driving staples into sheets from a front-end
portion of the series of staples; and
staple feeding means for feeding said series of staples from said staple
cartridge to said staple driving means,
wherein said sheet processing apparatus further comprises:
inhibiting means for inhibiting detachment of said staple cartridge;
detection means for detecting the absence at a predetermined position of
said series of staples; and
releasing means for automatically releasing the inhibition of said
inhibiting means when the absence of staples is detected by said detection
means.
2. An image forming apparatus including a sheet post-processing apparatus
comprising:
a stapling unit comprising:
a detachable staple cartridge for holding staples connected in series;
staple driving means for driving staples into sheets from a front-end
portion of the series of staples; and
staple feeding means for feeding the series of staples from said staples
cartridge to said staple driving means,
wherein said post-processing apparatus further comprises:
inhibiting means for inhibiting detachment of said staple cartridge;
detection means for detecting the absence at a predetermined position of
said series of staples; and
releasing means for automatically releasing the inhibition of said
inhibiting means when the absence of staples is detected by said detection
means.
3. A sheet processing apparatus comprising:
a stapling unit comprising:
a detachable staple cartridge; and
staple driving means for sequentially driving staples into sheets;
wherein said sheet processing apparatus further comprises;
inhibiting means for inhibiting detachment of said staple cartridge;
absence signal generating means for generating a signal indicative of an
absence of staples at a predetermined position of the staple; and
releasing means for automatically releasing the inhibition of said
inhibiting means in accordance with a signal from said absence signal
generating means.
4. An image forming apparatus including a sheet post-processing apparatus
comprising:
a stapling unit comprising:
a detachable staple cartridge; and
staple driving means for sequentially driving staples into sheets;
wherein said sheet post-processing apparatus further comprises;
inhibiting means for inhibiting detachment of said staple cartridge;
absence signal generating means for generating a signal indicative of an
absence of staples at a predetermined position of the staple; and
releasing means for automatically releasing the inhibition of said
inhibiting means in accordance with a signal from said absence signal
generating means.
5. A sheet processing apparatus comprising:
a stapling unit comprising:
a detachable staple cartridge for holding staples connected in series;
staple driving means for sequentially driving staples into sheets from an
front-end portion of the series of staples; and
staple feeding means for feeding the series of staples from said staple
cartridge to said staple driving means,
wherein said sheet processing apparatus further comprises:
cartridge regulating means engageable with said staple cartridge for
inhibiting detachment of said staple cartridge as a result of said
engagement;
driving means for moving said stapling unit between a stapling position and
a non-stapling position;
control means for controlling said driving means so as to move said
stapling unit to the stapling position when exchanging staples; and
releasing means for disengaging said cartridge regulating means from said
staple cartridge when said stapling unit moves to said stapling position.
6. A sheet processing apparatus comprising:
a stapling unit comprising:
a detachable staple cartridge for holding staples connected in series;
staple driving means for sequentially driving staples into sheets from a
front-end portion of the series of staples; and
staple feeding means for feeding said series of staples from said staple
cartridge to said staple driving means,
wherein said sheet processing apparatus further comprises:
cartridge regulating means engageable with said staple cartridge for
inhibiting detachment of said staple cartridge as a result of said
engagement;
detection means for detecting the absence at a predetermined position of
said series of staples; and
releasing means for automatically disengaging said regulating means from
said staple cartridge when the absence of staples is detected by said
detection means.
7. A sheet processing apparatus according to claim 6, wherein said
detection means detects the absence of staples when staples are completely
consumed and when staples remaining are below a predetermined amount.
8. A sheet processing apparatus according to claim 1, wherein said
cartridge regulating means engages at least one of electrically and
mechanically with the staple cartridge.
9. A sheet processing apparatus according to claim 6, wherein said stapling
unit is movable between a stapling position and a retracted position,
wherein said stapling unit moves to the stapling position when said
detection means detects an absence of staples, and
wherein said releasing means disengages the cartridge regulating means from
the staple cartridge as a result of the movement of the stapling unit.
10. A sheet processing apparatus according to claim 9, further comprising
means for guiding the staple cartridge so that a door is opened and the
staple cartridge can be taken out after the stapling unit has moved to the
stapling position.
11. An image forming apparatus including a sheet post-processing apparatus
comprising:
a stapling unit comprising:
a detachable staple cartridge for holding staples connected in series;
staple driving means for sequentially driving staples into sheets from a
front-end portion of the series of staples; and
staple feeding means for feeding the series of staples from said staple
cartridge to said staple driving means,
wherein said sheet post-processing apparatus further comprises:
cartridge regulating means engageable with said staple cartridge for
inhibiting detachment of said staple cartridge as a result of said
engagement;
detection means for detecting the absence at a predetermined position of
said series of staples; and
releasing means for automatically disengaging said regulating means from
said staple cartridge when the absence of staples is detected by said
detection means.
12. An image forming apparatus according to claim 11, wherein said
detection means detects the absence of staples when staples are completely
consumed and when staples remain below a predetermined amount.
13. An image forming apparatus according to claim 11, wherein said sheet
post-processing apparatus comprises a sheet sorter, and staples sheets
while sequentially facing each of a plurality of bin trays mounting the
sheets relative to the stapling unit, and wherein the stapling unit
performs reciprocating entering and retracting operations in accordance
with rise and descent of the bin trays.
14. A sheet processing apparatus comprising:
a stapling unit comprising:
a detachable staple cartridge; and
staple driving means for sequentially driving staples into sheet;
wherein said sheet processing apparatus further comprises:
cartridge regulating means engageable with said staple cartridge for
inhibiting detachment of said staple cartridge as a result of said
engagement;
absence signal generating means for generating a signal indicative of an
absence of staples at a predetermined position of the staple; and
releasing means for automatically disengaging said regulating means from
said staple cartridge in accordance with a signal from said absence signal
generating means.
15. An image forming apparatus including a sheet post-processing apparatus
comprising:
a stapling unit comprising:
a detachable staple cartridge; and
staple driving means for sequentially driving staples into sheets;
wherein said sheet post-processing apparatus further comprises:
cartridge regulating means engageable with said staple cartridge for
inhibiting detachment of said staple cartridge as a result of said
engagement;
absence signal generating means for generating a signal indicative of an
absence of staples at a predetermined position of the staple; and
releasing means for automatically disengaging said regulating means from
said staple cartridge in accordance with a signal from said absence signal
generating means.
16. A sheet processing apparatus comprising:
a stabling unit comprising:
a detachable staple cartridge for holding staples connected in series;
staple driving means for sequentially driving staples into sheets from an
front-end portion of the series of staples; and
staple feeding means for feeding the series of staples from said staple
cartridge to said staple driving means,
wherein said sheet processing apparatus further comprises:
cartridge regulating means engageable with said staple cartridge for
inhibiting detachment of said staple cartridge as a result of said
engagement;
driving means for moving said stapling unit between a stapling position and
a non-stapling position;
control means for controlling said driving means so as to move said
stapling unit to the non-stapling position when exchanging staples; and
releasing means for disengaging said cartridge regulating means from said
staple cartridge when said stapling unit moves to said non-stapling
position.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a sheet post-processing apparatus for aligning
and stapling sheets discharged from an image forming apparatus, such as a
copier, a printer or any other kind of recording apparatus, and to a
stapling unit for stapling a bundle of sheets.
2. Description of the Related Art
A conventional sheet stapling device (hereinafter termed a stapling unit)
includes a detachable staple cartridge providing a large capacity of
staples. If staples within the staple cartridge are used up, the staple
cartridge is replaced with a new one in order to supply staples.
The same configuration also is adopted in a sheet postprocessor (for
example, a sorter, a finisher or the like) wherein postprocessing of
sheets is automated by integrating a typical desktop stapler with an image
forming apparatus.
Although the above-described conventional device has the advantage that
suppling staples for the stapling unit is simplified by using the staple
cartridge which can be easily replaced, the device has the disadvantage
that since the staple cartridge is easily detached by anybody at any time,
the staple cartridge might be carelessly detached.
That is, in general, in the stapling unit used in the sheet postprocessor,
the staple cartridge is detached from the stapling unit only when a staple
sensor provided within the stapling unit detects the absence of staples.
In such a case, no problem arises if the staple cartridge is detached and
a new staple cartridge is loaded. However, when the staple cartridge is
detached from the stapling unit before it is empty, staples remain within
the stapling unit as well as within the staple cartridge. When a new
staple cartridge is subsequently loaded in the stapling unit, end portions
of staples remaining within the stapling unit might disturb or turn up
staples in the front end of the newly loaded staple cartridge. If the
staple cartridge is forcibly set in the stapling unit in that condition,
the disturbed staple belt might cause misfeeding of staples, jamming of
staples, or the like.
SUMMARY OF THE INVENTION
The present invention has been made in consideration of the above-described
problems in the conventional device.
It is an object of the present invention to provide a sheet postprocessor
which prevents disturbance of staples or occurrence of jamming of staples
within a stapling unit.
Referring, for example, to FIGS. 1, 2, 12 and 13, the above-described
object is accomplished, according to one aspect of the present invention,
by a stapling unit comprising a staple cartridge for holding a staple belt
connected in a line, movement regulating means received within the staple
cartridge for regulating movement of the staple belt, staple driving means
for sequentially driving the staple belt into sheets from a front-end side
of the staple belt, and staple feeding means for feeding the staple belt
from the staple cartridge to the staple driving means against a regulation
by the movement regulating means. The stapling unit further comprises
cartridge regulating means engageably movable relative to the staple
cartridge for regulating detachment of the staple cartridge by the
engagement, and staple detecting means. The cartridge regulating means
permits detachment of the staple cartridge when the staple detecting means
detects the absence of staples.
The cartridge regulating means moves so that the staple cartridge is
detached from the stapling unit when the stapling unit detects the absence
of staples.
According to the above-described configuration, detachment of the staple
cartridge in the stapling unit is regulated by the cartridge regulating
means. When the staple cartridge is permitted to be detached, the
cartridge regulating means is disengaged from the staple cartridge,
whereby the staple cartridge can be detached from the stapling unit.
When the staple detecting means detects the absence of staples in the
stapling unit, the cartridge regulating means is disengaged from the
staple cartridge so that the staple cartridge can be detached from the
stapling unit. Thus, even if the staple cartridge is loaded within the
stapling unit, the generation of disturbance of staples, jamming of
staples, and the like within the stapling unit is prevented, increasing
reliability of the stapling unit itself.
As explained above, according to the present invention, when the staple
detecting means detects the presence of staples in the staple cartridge of
the stapling unit, the staple cartridge is locked by the cartridge
regulating means, whereby detachment of the staple cartridge from the
stapling unit is prevented. When the staple detecting means detects the
absence of staples in the staple cartridge, the cartridge regulating means
is disenaged from the staple cartridge. Hence, the staple cartridge can be
detached from the stapling unit, whereby the generation of disturbance of
staples remaining in the stapling unit by a loaded staple cartridge
jamming of staples, and the like can be prevented. Hence, it is possible
to increase operability and reliability of the stapling unit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional side view of a sheet postprocessor according to an
embodiment of the present invention;
FIG. 2 is a view of the sheet postprocessor as seen from the direction of
arrow A shown in FIG. 1;
FIG. 3 is a perspective view of the sheet postprocessor;
FIG. 4 is a perspective view of a bin unit;
FIG. 5 is a sectional plan view of a lead cam/trunnion unit;
FIG. 6 is a sectional side view of the apparatus shown in FIG. 1 as seen
from the opposite side;
FIG. 7 is a side view of a flag portion of the lead cam;
FIG. 8 is a plan view of the flag portion of the lead cam;
FIGS. 9(a)-9(d) are side views showing the relationship between lead cams
and bins;
FIG. 10 is a plan view of a driving system for the lead cam;
FIG. 11 is a cam diagram of the lead cams;
FIG. 12 is a plan view of a stapling unit;
FIGS. 13(a) and 13(b) are side views of the stapling unit;
FIG. 14 is a perspective view of the stapling unit;
FIG. 15 is a plan view of a driving system for a bin unit;
FIG. 16 is a plan view of a sheet-aligning unit including an aligning
reference wall and an aligning member;
FIG. 17 is a block diagram illustrating a control device for the sheet
sorter of the present invention;
FIGS. 18(a), 18(b), 19, 20, 21, 22, 23, 24, 25, 26(a) and 26(b) are
flowcharts of the embodiment;
FIG. 27 is a sectional side view of lined-up sorters;
FIG. 28 is a plan view of the lined-up sorters;
FIG. 29 is a plan view of a conveying path for the lined-up sorters;
FIG. 30 is a plan view of the conveying path provided with an aligning
drive;
FIG. 31 is a side view showing a modified example of a lead-cam detecting
unit;
FIG. 32 is a plan view of the lead-cam detecting unit;
FIGS. 33(a) and 33(b) are flowcharts illustrating the operation of an
aligning bar; and
FIGS. 34(a) and 34(b) are side views illustrating another embodiment of an
opening operation of bins.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of the present invention will now be explained with
reference to the drawings.
In FIGS. 1 and 3, a bin-moving-type sorter (sheet postprocessor) I includes
a main body 7 of the sorter comprising a pair of right and left side
plates 3, a base 5, and a cover 6. The sorter 1 receives a group of bins B
comprising bins B1-Bn , and includes a bin unit 2 movable upward and
downward along a pair of guide rails 9 provided at the respective side
plates 3.
The main body 7 of the sorter is connected to an image forming apparatus M
disposed at a side upstream from the main body 7 (the right side in FIG.
1), and includes a carrying inlet 10 and a pair of carrying rollers 11 for
carrying a sheet P discharged from the image forming apparatrus M. In this
embodiment, image forming apparatus M comprises an original feeder R,
fixing rollers, a refeed path RP, a photosensitive drum and the like. A
first sheet-conveying path 12 and a pair of upper discharging rollers 13
are provided in sequence moving from the pair of carrying rollers 11
toward bin unit 2. Also provided is downwardly-directed second
sheet-conveying path 15 branching from the pair of carrying rollers 11 and
a pair of lower discharging rollers (sheet-discharging means) 16 facing
the bin unit 2. A deflector 17 is disposed at a branching portion of the
above-described two sheet conveying-paths 12 and 15. The deflector 17 is
selectively displaced so as to guide a sheet to be discharged into one of
bins B by the pair of upper discharging rollers 13 to the first
sheet-conveying path 12 and to guide a sheet to be discharged into one of
bins B from the pair of lower discharging rollers 16 to the second
sheet-conveying path 15.
A paper sensor 19 for detecting passage of sheet P is disposed near a
sheet-discharging portion of the second sheet-conveying path 15. Although,
in the present embodiment, the paper sensor 19 comprises a lead switch
incorporating a photo-interrupter, a transmission-type sensor may also
provide the same function. The sheet P discharged from an image forming
unit of the image forming apparatus M has been detected by a discharge
sensor disposed within the image forming apparatus M. In the present
embodiment, both the passing time of the sheet P and the interval (between
paper) between each successive sheet P can be measured. A calculation
circuit incorporated within the main body of the image forming apparatus
issues a discharge signal at the passing time of sheet P and an
interval-between-paper signal of the sheet P, and these signals are
transmitted to a microcomputer provided within the bin unit 2.
As shown in FIG. 3 or 4, the bin unit 2 includes a pair of bin-supporting
plates 20 having a frame structure at front and rear portions of the bin
unit 2. A bin slider 21 is mounted on a front end of each bin-supporting
plate 20. A bin cover 22 is fixed on the bin-supporting plates 20 and the
bin sliders 21. An aligning reference wall 23 is fixed between the bin
cover 22 and the bin-supporting plates 20. An aligning bar 26 is threaded
through notches 25 provided in each bin B so as to extend through the
entirety of bins B. The aligning bar 26 is swingable around a center bar
29 pivoting aligning bar 26 via a pair of aligning arms 27 connected at
the upper and lower portions of the aligning bar 26. The sheet P received
in each bin B is aligned by being pushed against the aligning reference
wall 23 by a swinging operation of the aligning bar 26.
Two free-end portions of each bin B received in the bin unit 2 are movably
mounted on comb-teeth-like grooves (not shown) in the bin sliders 21. As
shown in detail in FIG. 5, pins 30 are fixed to the right and left sides
of base-end portions of the bins B. The pins 30 are threaded through slits
31 provided in the right and left bin-supporting plates 20. Trunnions 33
are rotatably mounted on outer ends of the pins 30 via O rings 32, serving
as shock absorbers.
The trunnions 33 are fit in the guide rails 9 so that the trunnions 33 of
the respective bins B are piled up. The lowermost trunnions 33 contact
lower guide rollers 35 rotatably supported at the bin-supporting plates
20, and the uppermost trunnions 33 contact the upper guide rollers 36
rotatably supported at the bin-supporting plates 20. The respective bins B
are supported in the bin unit 2 so that the spacing between bins is
maintained constant and equal to the outer diameter of the trunnion 33.
As shown in FIG. 1, the bin unit 2 is configured to be able to rise and
descend along the guide rails 9 with the upper guide rollers 36 and the
lower guide rollers 35 fitted in the guide rails 9. Tension springs 39 are
stretched between metal fittings 37 fixed on the bin unit 2 and the side
plates 3 so as to upwardly pull the bin unit 2 by the elastic force of the
tension springs 39.
As shown in FIGS. 3 and 6, cam-shaft holders 40 are disposed at positions
facing the pair of lower discharging rollers 16 supported at the right and
left side plates 3, and lead-cam shafts 42 are rotatably disposed between
the cam-shaft holders 40 and the base plate 5 via bearings 41. A pair of
right and left lead cams (spiral cam means) 43a and 43b provided with
spiral cam surfaces are fixed at upper portions of the right and left
lead-cam shafts 42.
In FIGS. 6 and 10, a shift motor 45 rotatable in forward and reverse
directions is fixed at one of the side plates 3, and a bevel gear 46b
integral with a pulley 46a is fixed at one end of an output shaft 45a of
the shift motor 45. The pulley 46a is connected to a pulley 49 fixed on
the lead-cam shaft 42 of the lead cam 43b via a belt 47. A bevel gear 51
fixed on one end of a through shaft 50 meshes with the bevel gear 46b, and
bevel gear (not shown) integral with a pulley 53 meshes with a bevel gear
52 fixed on the other end of the through shaft 50. As shown in FIG. 10,
the pulley 53 is connected to a pulley 53 fixed on the lead-cam shaft 42
of the other lead cam 43a via a belt 55. According to the drive
transmission system configured as described above, when the shift motor 45
rotates in the forward or reverse direction, the lead cams 43a and 43b
rotate in the directions shown by the arrows in FIG. 10, or in directions
reverse to these directions.
A clock disk 56 is fixed on the other end (the lower end in FIG. 6) of the
output shaft 45a of the shift motor 45. An interrupter 59 held on one of
the side plates 3 by a sensor holder 57 can read the number of revolutions
of the shift motor 45, that is, the number of revolutions of the lead cams
43a and 43b. A lead cam control circuit within a microcomputer provided in
the sorter 1 can arbitrarily control the number of revolution of the lead
cams 43a and 43b.
As shown in FIG. 6, a pair of flags 61 and 62 for detecting the positions
of the lead cams 43a and 43b are coaxially fixed below the lead cam 43b on
the lead cam shaft 42. FIGS. 7 and 8 are enlarged views of the pair of
flags 61 and 62. In FIGS. 7 and 8, interrupters 63 and 65 for reading the
flags 61 and 62 are held by a holder 66 fixed on the side plate 3.
The interrupters 63 and 65 are arranged so as to have the same flag angle
with respective phases shifted by a predetermined amount. By on/off states
of the two interrupters 63 and 65 due to the shift in phases, it is
determined whether the bins B are in home positions in the rising
direction or in home positions in the descending direction, as will be
described later.
The lead cams 43a and 43b include parallel portions (about 180.degree.), as
will be described later. The phase shift between the flags 61 and 62 is
determined in accordance with the parallel portions. The phases of the
flags 61 and 62 are shifted by a predetermined angle (about 30.degree.).
By the on/off states of the interrupters 63 and 65 due to the shift of
angles between the flags 61 and 62, the positions of the lead cams 43a and
43b are determined.
Next, an explanation will be provided of the operation of the bins B
determined by the shapes of the lead cams 43a and 43b, and the trunnions
(bin rollers) 33 engaged with the lead cams 43a and 43b.
FIG. 9(a) illustrates the relationship among the left-side lead cam 43a,
the trunnions 33 and the bins B. FIG. 9(b) illustrates the relationship
between the right-side lead cam 43b and the trunnions 33. FIG. 10 is a
plan view of a drive transmission system for the lead cams 43a and 43b.
As shown in FIGS. 9(a)-9(d) and 10, in the present embodiment, directions
of respective screws of the lead cams 43a and 43b are reverse so as to
provide reverse directions of rotation, and the lead cams 43a and 43b are
mirror-symmetrical with each other. In the present embodiment, a
two-way-type configuration is adopted so that the spacing between bins B
can be expanded at two expanding portions X and X'. This is to allow a
sheet stapling mechanism to enter and retract from the bin B. If only the
sorting function is needed, only the expanding portion X in which the
sheet P is conveyed is required as the expanding portion.
When the lead cams 43a and 43b rotate in the directions of the arrows or in
directions reverse to those directions by the drive of the shift motor 45,
the trunnions 33 are pushed within grooves in the lead cams 43a and 43b,
and rise or descend guided by the guide rails 9. A deflected portion is
provided in part of each of the guide rails 9 shown in FIGS. 9(a)-9(d) in
order to displace the bins B in the back-and-forth direction (the moving
direction of the sheet) because the sorter 1 in the present embodiment
includes the sheet stapling mechanism 67. However, the present invention
is not limited to this configuration.
FIG. 11 illustrates a cam diagram of the lead cam 43a in the present
embodiment. In FIG. 11, hatched portions represent cam grooves in the lead
cam 43a. The cam diagram for the left side (the left side in the moving
direction of the sheet P) is shown. A cam diagram of the other lead cam
43b is mirror-symmetrical with this diagram. Since the above-described cam
diagram represents a range of 0.degree.-360.degree. and is a cam diagram
in the present embodiment, a cam diagram for two bins is shown.
The positions of the trunnions 33 within the grooves of the lead cam 43a
are represented by reference numerals 33a, 33b and 33c. A portion
represented by symbol H in FIG. 11 is a nearly-parallel portion of the
lead cam 43a. A parallel portion of about 180.degree. is set in the
present embodiment. In the above-described cam diagram, if the lead cam
43a moves to the right, that is, if the lead cam 43a rotates in the
direction of the arrow in FIG. 10 (the trunnions 33 perform relative
movement to the left in FIG. 11), the bins B rise. On the other hand, if
the lead cam 43a rotates counterclockwise (the trunnions perform relative
movement to the right), the bins B descend. The above-described parallel
portion H indicates the sheet discharging position of the lead cam 43a,
and inclined portions K indicate shift positions.
When the sheet P in FIG. 1 is discharged from the pair of lower discharging
rollers 16, the system is set so that a horizontal state (the parallel
portion H) is provided relative to the moving direction of the lead cam
43a. Hence, reference numeral 33x represents the home position when the
trunnions 33 rise, and reference numeral 33y represents the home position
when the trunnions 33 descend. In the present embodiment, the phases of
the home positions 33x and 33y are shifted by 180.degree., as shown in
FIG. 11. The positions 33x and 33y in the lead cam 43a correspond to flag
regions a and b shown in FIG. 8.
In the present embodiment, if an angle made by one circumference of the
lead cam 43 (43a and 43b) is represented by 2 .pi. (rad) , an angle made
by the parallel portion H is represented by .theta. (rad), and a time
during which the sheet P passes through the pair of lower discharging
rollers 16 is represented by t1, the number R1 (rpm) of revolutions of the
lead cam 43 can be expressed by the following expression (1):
R1=60.theta./2.pi.t1 (1)
Accordingly, the number of revolutions (the process speed) of the lead cam
43 increases as the discharging time of the sheet P becomes shorter.
If the time interval between passage of sheets P when the sheets P are
being continuously discharged from the image forming apparatus is
represented by t2 in order to adjust one revolution of the lead cam 43
with the discharging time of the sheet P + the time interval between
paper, the number R2 (rpm) of revolution of the lead cam 43 in the
remaining angle (2.pi.-.theta.) (corresponding to the inclined portion of
the lead cam 43a) must be:
R2=60 (2.pi.-.theta.)/2.pi.t2 (2)
If the angle .theta. made by the parallel portion H of the lead cam 43 is
set so that R1=R2, the revolution speed of the lead cam 43 becomes
theoretically constant during the discharging time of the sheet and the
time interval between paper, and it becomes therefore possible to shift
the bins B while receiving the sheet P in the bin B with rotating the lead
cam 43. That is, it is possible to achieve a sheet sorting function for
the sheets P discharged from the image forming apparatus in a state
wherein the lead cam 43 rotates at a constant speed.
When the image forming apparatus is a high-speed machine, in particular,
the value t2 is reduced. Hence, even if the number of revolutions of the
lead cam 43 is not constant, the lead cam 43 never stops, though its
number of revolutions may change, if a two-stage speed control from R1 to
R2 is performed. Thus, the sound typically generated by an impulsive force
corresponding to inertia of the bin unit accompanying the rotation and
stop of the lead cam in a bin-moving-type sorter of this kind is not
generated in the present embodiment. Hence, it becomes possible to design
a quieter sorter.
Another feature of the present embodiment is that the sorter of the present
embodiment is suitable for a high-speed (high-productivity) copier. That
is, if the set angle .theta. for the horizontal portion H of the lead cam
43 is more or less changed (for example, at least 180.degree.), the angle
of revolution of the lead cam 43 during the interval between paper is
proportionally reduced. Hence, even if the speed of revolution of the lead
cam 43 is considerably reduced, the sorter can be used for a machine
having higher speed (higher productivity) than a conventional copier.
Furthermore, since the on/off control (moving and stopping operation) of a
large unit such as the bin unit 2 is not performed, loss in the power
consumption of the copier can be reduced.
In the present embodiment, an explanation has been provided of a
configuration having two lead-cam flags 61 and 62. However, for example,
as shown in FIGS. 31 and 32, the same effect may be obtained even if a
single flag 290 and a single interrupter 291 are provided adjusted to the
parallel portions of the lead cams 43a and 43b.
In this case, determiation whether the bins B are at the home positions for
rise or descent is possible if data are stored in a microcomputer (not
shown) after the completion of the operation. If the power supply is
turned off and position information of the lead cams 43a and 43b is
cleared, by slightly rotating (initializing) the lead cams 43a and 43b and
recognizing whether an interrupter 301 is from an on-state to an off-state
or remains in an on-state, the positions of the lead cams 43a and 43b can
be determined. At that time, if a position detecting sensor for the bin
unit 2 is in a on-state, it is also possible to determine whether or not
the positions of the lead cams 43a and 43b correspond to the home position
of the bin unit 2.
A detailed explanation will now be provided of a stapler (a sheet-stapling
mechanism) in the present embodiment.
FIG. 2 illustrates the position of stapler 67 as seen from above. The
sheet-stapling mechanism 67 is configured so as to be able to advance
within and retract from the bin B of the sorter 1. FIGS. 12, 13(a) and
13(b) illustrate the configuration in more detail.
The stapler 67 indicated by two-dot chain lines in FIGS. 12 and 13(a) is a
conventional electrically-driven stapler, and comprises a staple-cartridge
unit 69 capable of receiving a large number of staples, a staple-feeding
unit 67a for sequentially feeding staples N from the staple-cartridge unit
69 to a stapling unit 67b, and the stapling unit 67b for stapling the
sheet P or the like using a fed staple to perform a stapling operation.
The stapling unit 67b includes a center 67c of rotation, and a stapling
operation is performed while an upper unit (movable in the directions Y in
FIG. 13(a)) and a lower unit of the stapler 67 sandwich the sheets P. A
stapler cover 70 for covering a motor and a driving system (not shown) is
screwed on a stapler attachment plate 71, which fixedly attaches the main
body of the stapler 67.
The stapler attachment plate 71 is fixedly screwed on a moving platform 72
for reciprocating the stapler 67. A moving guide 73 and a roller slider 75
are fixed on a lower portion of the moving platform 72. A driving force
from a stapler driving motor (not shown) is transmitted to a link gear 79
via gears 76 and 77. The link gear 79 includes a projection 79a engaged
with the roller slider 75, and is configured so as to rotate in the
direction A in FIG. 12.
The link gear 79 includes two microswitch actuating portions facing each
other. Since the projection 79a rotates 180.degree. for every
half-rotation of the link gear 79, the roller slider 75 can move a
distance corresponding to a rotation diameter of the projection 79a of the
link gear 79. The moving guide 73 enagages a guide shaft 81 mounted on a
stapler-fixing plate 80, and can move the moving platform 72 mounting the
stapler 67 in parallel in cooperation with the link gear 79.
A rotation-detecting microswitch 82 detects every half-rotation of the link
gear 79. A stapling-unit-position-detecting microswitch 83 engages a cam
85 mounted on a side surface of the moving platform 72, and is configured
so as to be switched off when the stapling unit is at a retracted position
67X retracted from the bin B, and switched on at other times.
A transmission-type paper sensor having a i-like shape and capable of
sensing the sheet P using upper and lower projections is provided at one
end portion of the moving platform 72, and is configured so as to be able
to detect the sheet P when the stapling unit reaches sheet-stapling
position 67Y. The above-described stapling unit and a unit capable of
reciprocating the stapling unit are fixed on the side plate 3.
A front-end side for receiving the sheet of a tapered guide 87 is tapered
so as not to turn up or shift the front end of the sheet P when the
stapling unit advances onto the sheet P (the sheet-stapling position 67Y).
The tapered-guide 87 is rotatable around an axis 87a of rotation, and a
rear-end portion 87b of the tapered-guide 87 is usually driven in a
counterclockwise direction by a spring means (not shown) so as to actuate
a stapler safety microswitch 89.
When, for example, the stapling unit advances onto the sheet P (the
sheet-stapling position 67Y), if a foreign substance (for example, a hand
of the operator) is placed on the bin or the stack of sheets P are thicker
than the stapling capability of the stapler 67, a moment raising the
front-end portion of the upper portion of the tapered guide 87 is produced
within the bin B and, with the lower unit portion 90 of the tapered guide
87 being fixed, the upper portion of the tapered guide 87 rotates in a
clockwise direction around the axis 87a of rotation, whereby the safety
microswitch 89 is switched off to mechanically cut off current supply for
the stapler 67.
An interlocking arm 91 having an axis 91a of rotation is provided on an
upper portion of the stapler cover 70. The interlocking arm 91 is usually
driven so as to rotate in a counterclockwise direction by a spring means
(not shown).
An actuating plate 92 provided on the side plate 3 is disposed above the
interlocking arm 91. In accordance with the reciprocating movement of the
stapling unit in the direction X shown in FIG. 13(a), the interlocking arm
91 is situated at a position indicated by solid lines when the stapling
unit is at the sheet-stapling position 67Y, and the interlocking arm 91
contacts the front-end portion of the actuating plate 92 when the stapling
unit is at the retracted position 67X, whereby, as shown by reference
numeral 91X, the lower portion of the interlocking arm 91 rotates over the
upper portion of the staple-cartridge unit 69 of the stapler 67 to depress
the staple-cartridge unit 69.
Next, an explanation will be provided of detection of staples in the
stapler 67.
In FIG. 13(a), there is shown a reflection-type staple sensor 93 indicated
by two-dot chain lines. When the last staple of staples provided in the
form of a sheet passes through the reflection-type staple sensor 93, the
sensor 93 detects the absence of staples. At that time, some staples in
the form of a sheet still remain downstream of sensor 93, and the front
end of the sheets to be stapled is held inside the stapler 67. When the
absence of staples has been detected, a manual stapling button 95 is
flashed, or a message indicating the absence of staples is displayed on a
display unit (not shown) of the image forming apparatus to urge the user
to exchange the staple cartridge. In the present embodiment, the system is
configured so that a stapling operation is prohibited when the
reflection-type staple sensor 93 has detected the absence of staples.
Although the absence of staples generally indicates that no staple N is
present within the cartridge, the concept of the absence of staples in the
present embodiment includes a state wherein a small amount of staples
remain to a degree of not requiring to exchange the staple cartridge.
An explanation will now be provided of exchange of a staple cartridge.
FIG. 14 is a schematic perspective view of the stapling unit of the sheet
postprocessor of the present embodiment. In FIG. 14, an openable and
closable door 96 is provided for the purpose of stapler maintenance and
replacement of a staple cartridge. The lower portion of the door 96
comprises a projection for actuating a door switch. There is also shown a
magnet catch 96b for holding the door. According to this configuration, if
the door 96 is closed in the direction of arrow O, a joint switch 99 is
switched on to permit the operation of the sorter 1.
In the present embodiment, if the door 96 is opened when the
reflection-type staple sensor 93 of the stapler 67 detects the presence of
staples, the stapler 67 is held at the retracted position 67X. At that
time, the interlocking arm 91 is in a position represented by reference
numeral 91X, that is, in a position wherein the lower portion of the
interlocking arm 91 is rotated and pushed up by the staple-cartridge unit
69 of the stapler 67.
As shown in FIG. 13(b), the staple cartridge 69 a transparent main body of
a case, a lower staple guiding path wall 69a extending from the main body,
a cover 69b and a spring 69c for pushing the staples N by being pressed by
the cover 69b. To remove staple cartridge 69 from the stapler 67, as
indicated by symbol Z in FIG. 13(a), the rear end of the cartridge 69 is
first raised, and the staple cartridge 69 is drawn out in the rear
direction after it has ridden over a rear-end stopper portion 67d of the
stapler 67. Hence, when the interlocking arm 91 is in the position
represented by reference numeral 91X, that is, when the stapling unit is
in the position represented by 67X (when the reflection-type staple sensor
93 detects the presence of staples), the staple cartridge 69 is
interlocked so as not to be removed from the stapler 67.
Software is provided so that, if the door 96 is opened when the
reflection-type staple sensor 93 detects the absence of staples (when the
joint switch 99 is switched off), tile staple unit automatically stops at
the position represented by reference numeral 67Y (see FIG. 2). Hence, the
staple unit moves and stops at the sheet stapling position 67Y (see FIG.
2).
When the stapling unit is at the above-described position, the interlocking
arm 91 is retracted from the upper portion of the staple cartridge 69, as
shown by solid Lines in FIG. 13(a), and the staple cartridge 69 can be
removed from the stapling unit by moving the rear end of the staple
cartridge 69 as indicated by arrow Z shown in FIG. 13(a). When the door 96
is closed (when the joint switch 99 is switched off), the stapling unit
returns to its standby position at the retracted position 67X (see FIG.
2).
In the present embodiment, when the door 96 is opened, if the staples are
present, the stapling unit does not move and remains at the retracted
position 67X. Alternatively, when the staples are present, the stapling
unit may be moved to the sheet stapling position 67Y so that the
interlocking arm 91 assumes the position represented by reference numeral
91X. When the staples are not present, the interlocking arm 91 may lock
the staple cartridge 69 while the stapling unit continues to stop. The
same effect may of course be provided by using an interlocking arm capable
of being switched on and off by the drive of a solenoid, a motor or the
like. For example, an electromagnet (a plunger) may be switched on in
accordance with the movement of the stapler toward the stapling position
to rotate the interlocking arm 91 in a clockwise direction, disengaging it
from staple cartridge 69.
As for the exchange of the staple cartridge, as described above, the
absence of staples is detected when the rear end of the staple belt within
the stapler passes the reflection-type staple sensor 93 in FIG. 13(a), and
the system is temporarily stopped. At that time, bundles of remaining
copies are automatically stapled after the supply of new staples.
Although, in the above-described embodiment, an explanation has been
provided of a mechanical engaging and disengaging operation, an electrical
engaging and disengaging operation may of course be performed. For
example, a configuration wherein locking is performed using a magnetic
force by an electromagnet may be adopted. In this case, the electromagnet
may be switched on and off in accordance with whether the stapler is at
the stapling position or at the retracted position.
Next, an explanation will be provided of alignment of the sheets P.
FIG. 16 is a transparent view of the bin unit 2 as seen from above. The
aligning reference wall 23 is provided as a reference for pushing the
sheets P thereagainst. The aligning bar 26 can perform a circular-are
movement around the center bar 29.
FIG. 15 illustrates a driving system disposed at a lowermost portion of the
aligning bar 26. In FIG. 15, a lower aligning arm 300 holds the aligning
bar 26 in cooperation with the upper aligning arm 27 (as shown in FIG. 3).
A leaf spring 301 can be deformed in a direction of moving the aligning
bar 26 to the right relative to the aligning arms 27 and 300 in FIG. 15.
A fan-like gear 301a for driving the lower aligning arm 300 and a flag 301b
for detecting the home position of the lower aligning arm 300 are provided
by being formed as one body at part of the lower aligning arm 300. There
are also shown a home-position sensor 302, a stepping motor 303 serving as
a driving source, and an idle gear 305. A torsional coil spring 306 is
hooked between the bin-supporting plate 20 and the lower aligning arm 300,
and regulates the backlash of the fan-like gear 301a and the idle gear 305
always in one direction so as to prevent vibration due to the backlash at
the transmission of normal and reverse drives of the stepping motor 303,
or at switching between normal and reverse drives, thereby reducing
operational noise. Furthermore, it has been confirmed by experiments that
a vibrational sound (for example, a clattering sound peculiar to the
stepping motor, or the like) is reduced by using a relatively soft resin
for the idle gear 305 meshing with a stepping-motor gear 303a.
Next, an explanation will provided of positions of the aligning bar 26 and
the aligning reference wall 23 when the sheet P is aligned.
First, the width of the sheet P is represented in FIG. 16 by x. For
example, the width x is 297 mm for the A4 size, and 210 mm for the A4R
size. In the present embodiment, a signal representing the size of the
sheet is determined by a paper-size signal of the image forming apparatus.
The value x also represents a distance between the aligning reference wall
23 and the aligning bar 26 when the sheet P is aligned.
Symbol "a" represents an amount of pushing of the sheet P by the aligning
bar 26 (the paper width-the aligning width). Although the width of the
sheet P is usually constant along its length, the width generally has some
variations, and an apparent paper width also varies in accordance with a
curled state of copying paper. Hence, the aligning bar 26 is pushed to a
position corresponding to a width smaller than the paper width when the
sheet P is aligned. In the present embodiment, the amount "a" is set so
that
a=.delta.cos .theta. (1)
where .theta. represents an angle of the aligning bar 26 relative to the
home position 26a (an angle when the end portion of the aligning bar 26
reaches position 26b at the end portion of the sheet), and represents an
amount of deflection of the leaf spring 301 in the direction Q, as shown
in FIG. 15.
In the present embodiment, the pushing force against the sheet P by the
aligning bar 26 is set to be the same for all sizes of the sheet P. This
is because, when the number of mounted sheets is small, if the pushing
force of the aligning bar 26 for the aligning arms 27 and 300 becomes
greater than a predetermined value, a pressed mark is left on the portion
of the sheet in contact with the aligning bar 26. When the pushing force
of the aligning bar 26 is near the predetermined value, an effect of
properly pushing the sheet P for aligning the sheet P is provided, thereby
increasing alignability of the sheets P.
The amount .delta. of deflection of the leaf spring 301 is expressed by the
following expression:
.delta.=4W1.sup.3 /bh.sup.3 E (2)
where W, 1, b, h and E represent a pushing force, the length of the leaf
spring 301, the width of the leaf spring 301, a leaf pressure by the leaf
spring 301, and modulus of longitudinal elasticity of leaf spring 301
(depending on the material of the leaf spring).
In the present embodiment, the value "a" when aligning the sheets P having
the A4 size (the standard size) is about 1.5 mm from experiments. As shown
by expression (1), the value "a" is reduced in the case of a size smaller
than the A4 size (but the pushing force is constant; W).
A tilt angle q of the aligning bar 26 corresponding to the size of the
sheet P is expressed by:
q=.pi./2=cos.sup.-1 {L0-x-r)/L} (3)
where .pi., L0 and r represent the circular constant, the distance between
the aligning reference wall 23 and the center bar 29, and the radius of
the aligning bar 26.
Hence, the value .theta. for each size is caculated by expression (3). By
inputting pulses for moving the lower aligning arm 300 by an amount
.theta.1 to the stepping motor 303, the movement of the aligning bar 26 is
achieved. Since the distance X between the end portion of the aligning bar
26 and the aligning reference wall 23 when aligning the sheet P is
expressed by:
X=x-a (4)
the value X is determined by a=.delta.cos .theta., where x represents the
width of paper.
If the value .theta.1 is further obtained, the number of pulses for the
stepping motor 303 is finally determined from information relating to
.theta.1. That is, the reason why the amount of pushing by the aligning
bar 26 is reduced as the width of the sheet P is reduced is that, when the
circular-arc-type aligning method as in the present embodiment is adopted,
the direction of pushing the sheet P by the aligning bar 26 approximately
equals the direction R shown in FIG. 16 for a wide size sheet (A4, A3 or
the like). This direction is approximately perpendicular to the aligning
reference wall 23, and no moment due to the pushing force is therefore
applied to the mounted sheets P. Hence, alignability of the sheets P is
not disturbed by the pushing force during the aligning operation.
On the other hand, in the case of a narrow size sheet (A4R, B5R or the
like), the direction of pushing the sheet P by the aligning bar 26 is
close to the direction S, and therefore has a certain angle relative to
the aligning reference wall 23. Hence, a rotational force against mounted
sheets P is applied. If the amount "a" of pushing exceeds a predetermined
value, the force has a function of inhibiting alignment of the sheets P
during the aligning operation.
In the present embodiment, an explanation has been provided of the
circular-arc-type aligning operation. The above-described amount "a" of
pushing having the predetermined value is also necessary for improving
alignability when an aligning bar or an aligning plate is urged in a
direction perpendicular to the aligning reference wall. The amount "a" of
pushing when the above-described aligning bar performs a parallel movement
need not vary in accordance with a change of paper width.
Next, an explanation will be provided of the movement of the aligning bar
26 when the sheets P are stapled.
In the present embodiment, after the completion of the sheet aligning
operation, and after all the copying sheets P have been discharged to the
sorter 1, it is possible to automatically perform stapling. In stapling,
the stapling unit moves in the sequence of the retracted position 67X to
the sheet stapling position 67Y for a stapling operation and back to the
retracted position 67X as shown in FIG. 2. As the stapling unit moves from
the retracted position 67X to the sheet stapling position 67Y, the
aligning bar 26 pushes the mounted sheets P against the aligning reference
wall 23.
When the stapling unit enters between respective piles of the mounted
sheets P, a pile of the sheets P moves between the upper unit and the
lower unit of the stapler 67 while contacting (not contacting in some
cases) the units via the upper tapered guide 87 and the lower tapered
guide 90, as shown in FIG. 13(a). Hence, in order to improve alignability
of the sheets P during the entering operation, the aligning bar 26 is in a
state of pushing the mounted sheets P during the entering operation of the
stapling unit.
In the present embodiment, the mounted sheets P slightly move by the
pushing force (direction) of the aligning bar 26 to minimize variations of
the position of the staple during a stapling operation. Hence, there is
provided a circuit which can control so that
a.gtoreq.a'(a'.div.0) (6),
where a' represents an amount of pushing during a stapling operation.
The above-described configuration is particularly needed in the
circular-are-type aligning method. In aligning the sheets P, if the number
of the sheets P on the bin B is small, for example, about 20, the sheets P
themselves whose stiffness in the width of the sheet P is greater than the
spring force of the leaf spring 301 of the aligning bar 26 way perform
extension/contraction movement by the pushing force of the aligning bar
26, or the entire sheets P may be twisted due to the moment produced by
the force in the direction S shown in FIG. 16.
On the other hand, if the number of the sheets P exceeds 20, a small amount
of misalignment may occur in some cases unless a certain amount of pushing
force is applied on the sheets P. This is because, in the present
embodiment, piles of the sheets P mounted in a plurality of bins (at least
ten bins) are aligned by the same aligning bar 26. In consideration of
parallelism of the aligning bar 26 from its upper and lower portions with
respect to the aligning reference wall 23, the above-described variations
(corresponding to the amount of tolerance in the width of the sheet P),
curled condition of respective piles of the sheets P in respective bins,
and the like, the amount "a" of pushing is also needed in alinging the
sheets P.
In a stapling operation, as described above, in order to suppress
variations in the stapled position, particularly in the case of a small
number of narrow sheets (for example, A4R or B5R), the amount a' of
pushing for minimizing disturbance of the sheets P when the stapling unit
enters between piles of the sheets P is needed.
Alternatively, an approach, wherein the amount "a" of pushing is reduced
when aligning a small number of sheets P, and the amount "a" is
automatically increased when the number of the sheets P reaches a certain
value (determined by a signal indicating the number of sheets from the
main body or the sorter), is also meaningful in order to improve
alignability. In the present embodiment, the above-described certain value
corresponds to when the elastic force of the aligning arm and the leaf
spring nearly equals the stiffness of the entire mounted sheets. The
above-described configuration may of course be applied also for a
parallel-moving-type aligning means.
An explanation will now be provided of a series of operations wherein the
sheets P are carried from the image forming apparatus within the sorter 1
and discharged in the bins B, the bins B are shifted, and the sheets P are
aligned and stapled.
First, the sheet P discharged from the image forming apparatus M connected
to the sorter 1 (see FIG. 1) is carried from the carrying inlet 10, and is
discharged in the bin B via the the pair of carrying rollers 11 and the
deflector 17. In this discharging operation of the sheet P, in nonsorting,
the sheet P is discharged from the pair of upper discharging rollers 13 in
the bin B. In the sorting operation, the sheet P is discharged in the bin
B from the pair of lower discharging rollers 16 via the second sheet
conveying path 15.
Using a paper-discharge signal from the image forming apparatus, a passing
time of the sheet P and an interval (between paper) between passage of
consecutive sheets P are measured. The measured information is transmitted
to a microcomputer provided within the bin unit 2.
If the time for detecting the sheet P exceeds a predetermined time from the
previous sheet detection time due to occurrence of a failure in sheet
conveyance, or the like, or if the next sheet P cannot be detected within
a predetermined time, a stop/delay jam signal identical to that from a
conventional jam sensor is issued for a microcomputer within the main body
of the image forming apparatus, whereby the entire system is stopped.
The passing time of the sheet P and the interval between paper are
measured. A microcomputer within the sorter 1 receiving that information
recognizes a discharging time of the sheet P (a time during which the
sheet P is discharged to the sorter 1) and the interval between paper. The
rotation speed of the lead cam 43 is measured and position control of the
lead cam 43 is performed using the above-described data. The position
control of the lead cam 43 is performed by synchronizing the discharging
timing of the sheet P within the bin B with the starting timing of the
horizontal portion H (see FIG. 11) of the lead cam 43.
As described above, it is possible to recognize the speed of the lead cam
43 using the clock disk 56 (see FIG. 6) provided on the output shaft 45a
of the shift motor 45 for driving the lead cam 43 and the interrupter 59,
and to recognize one end and the other end of the approximately parallel
portion H of the lead cam 43 using the flags 61 and 62 (see FIGS. 7 and 8)
provided at the lower portion of the lead cam shaft 42.
For example, the number of revolutions of the lead cam 43 may be set so
that, in a sorting operation with the bin unit 2 rising, discharging of
the sheet P is started when the trunnion 33 of the bin B in which the
sheet P is to be received reaches the home position 33x shown in FIG. 11,
and discharging of the sheet P is completed while the trunnion 33 moves
from the home position 33x to the position 33y.
The bin unit 2 is further shifted between the positions 33y and 33z. Since
the interval between paper has been recognized using the above-described
information, the trunnion 33 may perform rotation from the positions 33y
to 33z within the interval between paper. At that time, the next bin B has
already arrived at the position 33x, and the next sheet P is received.
This operation is repeated for respective bins B.
In sorting with the bin unit 2 descending, discharging of the sheet P is
started when the trunnion 33 of the bin B in which the sheet P is to be
discharged reaches the position 33y, and discharging of the sheet P is
completed while the trunnion 33 moves from the position 33x to the
position 33y. The trunnion 33 rotates from the positions 33x to 33y within
the interval between the discharged sheets P. At that time, the next bin B
has already arrived at the position 33y. This operation is repeated for
respective bins B.
During discharging operation of the sheets P, variations in the process
speed of the main body of the image forming apparatus, in the interval
between paper, and the like are detected and transferred from the main
body of the image forming apparatus to the microcomputer of the bin unit 2
whenever any such variation occurs. Hence, speed control of the trunnion
33 is always subjected to feedback control according to new information.
According to the above-described configuration of the sorter 1, it is
possible to deal with a difference in the discharging time due to a change
in the size of the sheet P. Furthermore, even if the sorter 1 is connected
to different image forming apparatuses having different process speeds and
different intervals between paper, each image forming apparatus can
perform optimal lead cam control. Hence, the sorter (sheet postprocessor)
1 can stably deal with a wide range of apparatuses.
Next, an explanation will be provided of sheet discharging and sheet
alignment.
The sheet P discharged from the image forming apparatus and carried from
the carrying inlet 10 is discharged from the pair of lower discharging
rollers 16 in sorting.
During a sheet discharging operation, the bin B into which the sheet P is
being discharged stops opposite to the pair of lower discharging rollers
16 (at that time, the lead cams 42a and 42b rotate, and the trunnion 3
passes the parallel portion of the lead cam). In normal sorting (wherein
the bin unit 2 receives the sheets while moving from below to above),
after the sheet discharging operation, the lower bin B which has received
the sheet P rises at a predetermined time period ti after a sheet
discharging signal has been detected by the paper sensor 19 and the rear
end (in the direction of sheet conveying direction) of the sheet P has
passed a nip portion of the pair of lower discharging roller 16, and the
next bin B stops at a position facing the pair of lower discharging
rollers 16.
The bin Bb which has received the sheet P see FIG. 9(a)) rises along the
inclined portions K of the lead cams 42a and 42b. At that time, the space
between the bin Bb and the tipper bin Ba gradually narrows. Accordingly,
before the bin Bb has shifted and reached the position of the bin Ba, and
the bin interval becomes narrow as indicated by symbol C, the aligning bar
26 pushes the sheet P discharged in the bin Bb so as to bring sheet P in
contact with the aligning reference wall 23, and sheet aligning is thus
terminated.
If the number of mounted sheets P is small, sheet aligning may be performed
after the shift of the bin Bb has been completed to minimize the space
between the bin Bb and the upper bin Ba, since the space between the bins
is greater than the thickness of the pile of the sheets P and therefore
alignment is possible. However, when a larger amount of sheets P are
mounted and particularly when curling of the sheets P is great, it becomes
difficult to completely push and align the discharged sheet P, since the
mounted height of the pile of the sheets P becomes in some cases greater
than the space C.
That is, if the condition shown in FIG. 9(a) is provided when the
discharged sheet P is not pushed by the alinging bar 26, the entire stack
of sheets P are pressed from above and below by the bins Ba and Bb. At
that time, aside from already aligned sheets P, an end portion of the
sheet P immediately after being discharged (the sheet P which is not yet
pushed against the aligning reference wall 23 ) may be deflected, or the
sheet P may have a pressed mark, while the sheet P is not aligned due to
the above-described load of the bins, causing insufficient alignment.
Accordingly, in the present invention, the discharged sheet P is aligned by
the aligning bar 26 as the bin B shifts from the position Bb to the
position Ba (that is, while the bin space C is wide). More preferably,
aligning must be completed before the bin B completes to shift up after
the discharged sheet P returns and contacts a front end stopper B' of the
bin tray. Thus, the interval between sheets can be shortened, contributing
to high-speed processing. In the case of rise, however, since the bin tray
shifts in a direction separated from the discharging inlet to approach the
discharged sheet, alignability is not significantly impaired even if the
sheet P is pushed by the aligning bar 26 before the sheet P contacts the
front-end stopper B' of the bin tray.
In reverse sorting (wherein the bin descends after receiving the sheet P),
as shown in FIG. 9(a), the sheet P is discharged in the bin Bb, which
moves to the position of the bin Bc. In this case, the discharged sheet P
is aligned by the aligning bar 26 after the sheet P has been discharged
and the bin Bb has moved to the position of the bin Be.
When the bins B move in the descending direction, the angles of the bins Bb
and Bc differ from each other, as shown in FIG. 9(a). Hence, if aligning
is performed while the bin Bb moves from the positions Bb to Bc, wherein
already-aligned mounted sheets (the already-aligned sheets are also pushed
by the aligning bar 26 when the discharged sheet is aligned) are pushed
while the angle of the mounted sheets P changes (while the bins B
descend), misalignment occurs. Accordingly, during the descending movement
of the bins B, the aligning bar 26 aligns the discharged sheet P after the
bin Bb has shifted down from the position Bb' to the position Bc'.
The above-described misalignment occurs because, if the sheet P is pushed
while the sheets P in the bin B are descending, the sheet P floats from
the bin B, and is deflected and disturbed. In the above-described aligning
operation of the sheet P, since the space D between the bins Bb and Bc is
widened in the case of the descending movement of the bins B, it is
possible to stack a sufficient amount of sheets P even if curling of the
sheets P is great, in contrast to the case of the rising movement of the
bins B.
As another approach, after discharge of the sheet P into bin Bb, the bin Bb
may rise or descend after aligning the sheet P, and move to the positions
Ba and Bc in normal and reverse sorting operations, respectively. Also in
this approach, the sheet P can be mounted and aligned. In this case,
unless the sheet P is aligned after the rear end of the discharged sheet P
has contacted the stopper member B' of the bin B, alignability of the
sheet P is reduced (mounted by being twisted) due to a moment applied to
the sheet P when the aligning bar 26 pushes the sheet P. Accordingly,
alignment must be performed after the sheet P contacts the stopper unit
B'.
By moving the bin B after the discharged sheet P has been correctly
aligned, it is also possible to align the sheets P within the bin B. In
this case, although an image forming apparatus having a slow process speed
and a long interval between paper can be dealt with, a high-speed machine
(at least 60 cpm (copies per minite)) having a high process speed and a
short interval between paper cannot be dealt with if the bin is shifted
after waiting the above-described time. Hence, the above-described
configuration of the present embodiment is needed.
The above-described timing of alignment is determined by counting a
predetermined time period by a counter after detecting the sheet P by a
sensor.
Next, an explanation will be provided of a stapling operation of the sheets
P after alignment.
In the present embodiment, when all copying sheets are discharged and
aligned within the bins B, the stacks of the sheets B are stapled
sequentially from -the last bin B in which the sheets P have been aligned.
The above-described processing will now be briefly explained. After the
last sheet has been aligned, the aligning bar 26 pushes again the mounted
bundle of sheets (the entirety of sheets within the bin) against the
aligning reference wall 23. At that time, because of the above-described
reason, in the present embodiment, the amount of pushing by the aligning
bar 26 is smaller than during alignment (the amount "a" of pushing during
alignment is arranged so that "a"=0). According to the above-described
configuration, alignability is improved from a small number of sheets P to
a large number of sheets P.
As described above, the entire stack of sheets P are held by the aligning
bar 26. A curling suppressor, (not shown) for the sheets P is disposed
near the sheet inlet having the upper tapered guide 87 and the lower
tapered guide 90 at the opening of the stapling unit. The curling
suppressor regulates mainly a sheet P having a large degree of upper
curling to maintain it lower than a predetermined amount (a height from
the surface of the bin B to a taper-starting portion of the upper tapered
guide 87).
In this condition, the stapling unit having the above-described
configuration moves from 67X to 67Y in FIG. 2. At that time, upper curling
of the sheets P on the bin B is regulated by the curling suppressor. Lower
curling hanging from the end portion of the bin B is raised by the tapered
portion of the upper tapered guide 90, and the apex portion of the lower
tapered guide 90 functions as a jump platform so that the sheets P are not
caught in the opening of the stapler 67. According to this configuration,
it is possible to stably advance the sheets P mounted on the bin B into
the opening of the stapler 67 even if the sheets P have upper or lower
curling.
When the stapling unit reaches the position 67Y, the sheets P are detected
by the transmission-type sensor 86 (FIG. 12), and the sheets P are stapled
only when the sheets P are mounted on the bin B. After the completion of
stapling of the sheets P, the stapling unit returns again to the retracted
position 67X where the stapling unit does not interfere with the sheets P
on the bin B even if the bin B shifts.
When the stapling unit returns to the retracted position 67X, a
stapling-unit-position-detecting microswitch 83 is switched off to permit
the shift motor 45 to rotate. The bin unit 2 is thereby shifted up or
down, and a stapling operation for the next bin B is started in the same
manner as described above.
If the bin B shifts when the stapling unit is at the position 67Y, the
front end of the stapling unit may interfere with the sheets P and the bin
B and damage the sheets. Accordingly, a current supply circuit for the bin
unit is mechanically connected only when the
stapling-unit-position-detecting microswitch 83 is switched off so that a
bin-shifting operation is never performed when the stapling unit is at the
position 67Y even if software erroneously instructs it to do so.
When the stapling operation is started under circumstances, for example,
where the stapling unit malfunctions, or the number of sheets P in bin B
exceeds a staplable amount, and the stapler 67 stops during the operation
due to overload, if the stapling unit returns to the position 67X and the
bin B shifts in that state, the sheets P may be torn. In such a case, a
one-revolution (one-process) sensor (not shown) mounted in a timer circuit
within the stapler 67 detects that the stapler 67 does not return to the
home position within a predetermined time period after starting the
operation. The stapler 67 is then returned to the home position by being
rotated in a direction reverse to one revolution (in the direction to
operate the spring) of the stapler 67. Subsequently, the stapling unit is
returned to the position 67X.
In this case, since the stapling unit cannot perform one revolution in a
predetermined direction, a stapler abnormal signal is issued from a
control circuit (not shown), and abnormality is displayed on a display
unit or the like on the main body of the image forming apparatus.
In the present embodiment, if the drive of the stapler has been reversed,
it is assumed that the stapling unit is abnormal, and an abnormal signal
is issued. However, for example, even if the stapling unit is reversely
rotated and returns to the home position, the stapling unit resumes in
some cases a normal operation after another revolution in a predetermined
direction. That is, when a staple is abnormally fed only once, if the
stapler 67 is reversely rotated while locking only one process, the next
stapling process returns in some cases to a normal state.
In such a case, since it is improper to determine to stop the system
(failure in stapling) with issuing an abnormal signal according to only
one reverse revolution of the stapler 67, the number of the reverse
revolution may be increased to at least two, or the number of processes
for determining abnormality may of course be increased to two or three.
For example, if the stapler 67 is reversely rotated at the first bin B,
the bin B may be shifted, and the stapling operation for the next bin B
may be started in order to perform a second trial. At that time, if the
stapler 67 normally performs a one-revolution stapling operation, the
system will be continued. If the stapler 67 is reversely rotated also the
second time, an abnormal signal of the stapling operation will be issued
at that time.
Next, an explanation will be provided of a lined-up operation of the
sorters.
FIG. 27 is a schematic cross-sectional view of two lined up sorters. In the
present embodiment, a sorter 1 (in the first line) and a sorter 100 (in
the second line) are entirely the same. By connecting the two identical
sorters in series, twice the amount of copying paper as when a single
sorter is used can be received.
FIG. 28 is a view of the lined-up sorters as seen from above. In the
present embodiment, the sorters 1 and 100 are connected by screwing rail
members 101 and 102 on the front side X and the rear side Y of the sorters
1 and 100.
Communication and electric power supply between the first and second
sorters are performed via cords drawn from power-supply-cord mounts (not
shown) each provided at a rear portion of each of the sorters 1 and 100.
By inserting the cord of the sorter 100 in a connector of the
power-supply-cord mount of the sorter 1, and inserting the cord of the
sorter 1 in a connector of a power-supply-cord mount (not shown) provided
at a rear portion of the image forming apparatus, information and electric
power are supplied and transmitted in the sequence of from the image
forming apparatus to the sorter 1 to the sorter 100.
The present embodiment has the advantage that any number of a plurality of
sorters may be connected as long as power supplies permit. Although, in
the present embodiment, two sorters are lined up, even three or four
sorters may be lined up so that a larger amount of copying paper can be
received in the sorters provided that space and a power supply for
installing the sorters are available.
Next, an explanation will be provided of the configuration of a paper path
between the sorters 1 and 100. In the present embodiment, connecting stays
105 are disposed at lowermost portions of the bins B. Trunnions 33' are
rotatably supported at side portions of the connecting stays 105, and a
connecting conveying path unit 200 is detachably mounted on the connecting
stays 105 by being screwed or by any other holding means.
According to the above-described configuration, when the trunnions 33' at
the side portions of the connecting stays 105 rise or descend by the lead
cams 42a and 42b, the connecting conveying path unit 200 can also rise or
descend, and it can rise to a predetermined position and receive the sheet
P at a position (the position where the bin B receives the sheet P; the
parallel portions of the lead cams) facing the pair of lower discharging
rollers 16 of the sorter 1.
Next, the configuration of the conveying path unit 200 will be explained.
In FIG. 29, there is shown an entrance guide 201 of the connecting
conveying path unit 200, and also entrance weights 202 for conveying the
sheet P. A leaf spring 203 is provided at a front-end portion of each of
the entrance weights 202, and is usually in pressure contact with the
upper bin B to guide insertion of the sheet P when the two sorters are
lined up.
FIG. 29 is a plan view of the connecting conveying path unit 200. In FIG.
29, rubber belts 205 are stretched between roller shafts 206 and 207. A
timing belt 208 is stretched between a pulley 209 of the shaft 207 and a
pulley 210 of a motor 211. The roller shaft 207 and the rubber belts 205
are driven by the rotation of the motor 211 via the timing belt 208.
The entrance weight 202 and an intermediate weight 204 both swingable
around a shaft 208 are provided on each of the rubber belts 205. The sheet
P discharged by the pair of lower discharging rollers 16 is conveyed onto
the rubber belts 205 by the entrance guide 201, and is conveyed toward a
downstream side by the entrance weights 202 and the intermediate weights
204. Paper-discharging rollers 212 are disposed at an output portion of
the conveying path unit 200, and have the function of guiding the sheet P
to an inlet 103 of the sorter 100.
In the case of using a sorter where the aligning bar 26 is threaded within
the bin unit and sheets P can be aligned, a unit for driving the aligning
bar 26 is provided at a lower portion of the connecting conveying path
unit 200. A portion in the connecting conveying path unit 200
corresponding to an operational region of the aligning bar 26 is cut as in
the bin B. In order to improve sheet conveyability of a cut portion, as
shown in FIG. 30, a smooth sheet guide 216 is screwed (screws are buried
below the conveying path so as not to interfere with the sheet P) or fixed
by any other means in the cut portion.
Next, the flow of the sheet P to the connecting path will be explained.
In the present embodiment, when preparing a number of copies greater than
the number of bins in a single sorter, for example, when the first sorter
has n bins and n+.alpha. bundles of copies are to be made, the first
sorter completes stapling of n bundles. The first sorter then performs a
(n+1) bin shift, and the connecting conveying path unit 200 is shifted to
a position facing the pair of lower discharging rollers 16, as described
above. Subsequently, sorting (or grouping) of remaining bundles of copies
is performed, and a stapling operation is completed if necessary.
During the above-described operation, the bundles of copies subjected to
postprocessing in the first sorter may be taken out. If the relationship
between the above-described n and .alpha. is that n<.alpha.,
postprocessing (sorting or grouping/stapling) for the remaining bundles is
automatically performed again in the first sorter after the completion of
postprocessing in the second sorter. At that time, transmission-type
through-bins sensor 400 and 400' (see FIG. 4) deter-mine whether any
remaining bundles of sheets from the preceding processing in the first
sorter remain. The postprocessing is automatically started only when no
sheets P remain in the bins B. If any sheets P remain in the bins B,
postprocessing is not started until the user removes all remaining sheets.
The first advantage of the present configuration is that an infinite number
of necessary copies may be set in the image forming apparatus.
Postprocessing is performed in units of n bins for receiving sheets per
sorter, and is performed in the sequence of the first sorter, followed by
the second sorter, and then followed by the first sorter. While the first
sorter performs postprocessing, bundles of sheets received in the second
sorter and subjected to postprocessing are removed. After removing the
bundles of sheets, postprocessing in the second sorter is automatically
resumed after the completion of postprocessing in the first sorter. Thus,
the system may form an infinite loop. The present configuration may be
applied for at least two sorters, or even for a single sorter. In the case
of using a single sorter, after n bundles of copies corresponding to the
number of bins have been prepared, all sheets P are removed. Subsequently,
postprocessing is automatically started to prepare bundles of remaining
copies.
When the above-described lined-up sorters are connected to an image forming
apparatus having an original feeder provided with a reservation function
for originals, it is necessary to deal with users of an original receiving
shelf of the original feeder, a receiving shelf of a reservation device
and the like.
For example, the following approach is possible: Preparation of bundles of
copies from an original in the original receiving shelf is started in the
first sorter. After the completion of the preparation of the bundles,
postprocessing for bundles of copies from an original in the receiving
shelf of the reservation device is automatically performed in the second
sorter. A first user can take out the bundles of copies from the first
sorter when the copying operation of his own original has been completed
(even if postprocessing for copies of a second user is performed in the
second sorter). When the first user has taken out his bundles of copies,
the first sorter can deal with a third user who has placed his original in
the receiving shelf of the reservation device. Thus, it is possible to
expand the system.
The first and second sorter may have a stapling function as in the present
embodiment, or may not have a stapling function. Alternatively, only the
first sorter may have a stapling function, and the second sorter may not
have a stapling function, or vice versa. When the first and second sorters
have a stapling function, and for example, copying is performed in an
autostapling mode, if staples are exhausted in the first sorter but are
present in the second sorter, the absence of staples in the first sorter
is detected, and the autostapling mode is automatically started in the
second sorter.
As shown in FIG. 17, the sorter 1 shown in FIG. 1 includes a control device
comprising a central processing unit (CPU) 111, a read-only memory (ROM)
112, a random access memory (RAM) 113, an input port 114, and an output
port 116. The ROM 112 stores control programs. The RAM 113 stores input
data and data for operations. A number of sensors, such as a
nonsorting-path sensor S1 and the like, and a door switch S12 are
connected to the input port 114. Loads, such as a conveying motor 117 for
driving the pair of carrying rollers 11 and the pair of lower discharging
rollers 16, are connected to the output port 116. The CPU 111 controls the
respective units connected thereto via a bus in accordance with control
programs stored in the ROM 112. The CPU 111 includes a serial interface to
perform, for example, serial communication with a CPU of the main body of
the copier, and controls the respective units according to signals from
the main body of the copier.
The operation of the present embodiment will now be explained according to
the flowcharts shown in FIGS. 18(a) through 24.
First, as shown in FIG. 18(a), if, for example, a copy-start key on the
main body of the copier is depressed to start a copying operation, a
sorter start signal is transmitted from the main body of the copier in the
form of a serial signal. The sorter 1 has been waiting for the signal
(Step 101). When the sorter start signal has been transmitted, the program
proceeds to Step 102. At Step 102, the mode of an operation for a time
period of one job until the sorter start signal disappears is determined,
and mode data is stored in the RAM 113. In order to detect the position of
the aligning bar 26, the aligning bar 26 is first returned to the home
position (Step 103). Subsequently, respective units are operated according
to the mode determined at Step 102. That is, at Step 104, it is determined
whether or not the current mode is a nonsorting mode. In the case of the
nonsorting mode, it is determined whether or not stapling is to be
performed (Step 105). The program proceeds to a stapling nonsorting mode
when stapling is to be performed (Step 107), and the program proceeds to
the nonsorting mode when stapling is not to be performed (Step 108). If it
has been determined that the current mode is not the nonsorting mode at
Step 104, the program proceeds to Step 106, where it is determined whether
or not the current mode is a sorting mode. In the case of the sorting
mode, the process proceeds to Step 109 for the sorting mode. When the
current mode is not the sorting mode, the current mode is determined to be
a grouping mode, and the program proceeds to Step 110. After the
completion of the operation at any of the above-described modes, the
program proceeds to Step 111, where it is determined whether or not a
sorter start signal is present, that is, whether one job has been
completed. When a sorter start signal is present, it is determined that
one job is not completed, and the program returns to Step 104. When a
sorter start signal is not present, it is determined that one job has been
completed, and the program proceeds to the initial Step 101.
In an alternative approach, as shown in FIG. 18(b), if it has been
determined that a sorter start signal is absent at Step 101, the program
proceeds to Step 120, where it is determined whether or not the door 97 of
the stapling unit is open. If the door 97 is closed, the program proceeds
to Step 121, where the stapler 67 is retracted, and the program returns to
Step 101. On the other hand, if it has been determined that the door 97 of
the stapling unit is not closed at Step 120, the program proceeds to Step
122, where it is determined whether or not the staple supply is exhausted.
If staples are absent, the program returns to Step 101. If staples are
present, the stapler 67 is moved to the operating position (Step 123), and
the interlocking mechanism of the staple cartridge 69 is released.
FIG. 19 shows the operation in the stapling nonsorting mode.
The position of the bin unit 2 in the stapling nonsorting mode is the home
position. At Step 201, the bin unit 2 is moved to the home position. At
that time, the stapler (sheet stapling mechanism) 67 cannot staple sheets
mounted on the bin cover 22, but staples the sheets P received in the bin
B. When the stapling mode is selected, even in a nonsorting state, it is
necessary to provide the sheets P in the bin B. Hence, the flapper
solenoid 122 is turned off, and the discharging port for sorting (the pair
of lower discharging rollers) 16 is selected (Step 202). Subsequently, it
is awaited until a size-determining signal arrives (Step 203). If a
size-determining signal arrives, the program proceeds to Step 204. At Step
204, data of the paper size transmitted from the main body of the copier
is stored in the RAM 113. If the sheet discharged from the main body of
the copier is the first sheet (Step 205), the aligning bar 26 which must
be at the home position is moved to an edge-aligning position 26a (Step
206). When it has been determined that the discharged sheet is not the
first sheet at Step 205, or after the aligning bar 26 has been moved to
the edge-aligning position 26a at Step 206, the program proceeds to Step
207. At Step 207, the program waits until a paper-discharging signal for
the main body of the copier is received. If a paper-discharging signal
arrives, the aligning bar 26 is moved from the edge-aligning position 26a
to the waiting position 43b (Step 208), the sheet is conveyed within the
bin B (Step 209), the aliging bar 26 is moved to the edge-aligning
position 26a to align the sheet (Step 210), and the program proceeds to
Step 211. At Step 211, it is determined whether or not a stapling signal
is present. If the result of the determination is affirmative, a stapling
operation is performed (Step 211). If the result of the determination is
negative, the program returns to the main routine.
Next, the operation in the nonsorting mode will be explained with reference
to FIG. 20.
In the nonsorting mode, since the sheet is discharged onto the bin cover
22, the bin unit 2 is moved to the lowermost position, which is the home
position (Step 310), and the flapper solenoid 122 is turned on in order to
discharge the sheet from the paper discharge rollers 13 for nonsorting
(Step 311). Subsequently, the program waits until a size-determining
signal arrives (Step 312). If a size-determining signal arrives, the size
is determined (Step 313), and the program proceeds to Step 314. At Step
314, a paper-discharging signal from the main body of the copier is
awaited. If a paper-discharging signal arrives, the program proceeds to
Step 315, where the sheet is discharged onto the bin cover 22, and the
program returns to the main routine,
Next, the operation in the sorting mode will be explained with reference to
FIG. 21.
First, it is determined whether or not a bin-initializing signal from the
main body of the copier signals that bin unit 2 must be returned to the
home position (Step 401). The bin unit 2 is moved to the home position
only when a bin-initializing signal is present (Step 402). Subsequently,
the flapper solenoid 122 is turned off in order to select the discharging
outlet 16 for sorting (Step 403), and the program proceeds to Step 404. At
Step 404, the program waits until a size-determining signal arrives. If a
size-determining signal arrives, the program proceeds to Step 405. At Step
405, the size is determined. Subsequently, it is determined whether the
size determination is for the first sheet (Step 406). The aligning bar 26
is moved to the edge-aligning position 26a only in the case of the first
sheet (Step 407), and the program proceeds to Step 408. At Step 408, a
paper-discharging signal from the main body of the copier is awaited. If a
paper-discharging signal arrives, the aligning bar 26 is moved to the
waiting position 43b (Step 410). Subsequently, a conveying operation for
discharging the sheets within the bins B is performed (Step 411), the
aligning bar 26 is moved to the edge-aliging position 26a (Step 413), and
the program proceeds to Step 414. At Step 414, it is determined whether or
not a stapling signal is present. A stapling operation is performed only
when a stapling signal is present (Step 415), and the program returns to
the main routine.
The movement of the bins B in sorting will be further described later.
Next, the operation of the grouping mode will be explained with reference
to FIG. 22.
First, it is determined whether or not a bin-initializing signal from the
main body of the copier is present (Step 501 ). The bin unit 2 is moved to
the home position only when a bin-initializing signal is present (Step
502). Subsequently, the program waits until a size-determining signal
arrives (Step 503). If a size-determining signal arrives, the program
proceeds to Step 504. At Step 504, the size is determined. Subsequently,
it is determined whether the size determination is for the first sheet
(Step 505). The aligning bar 26 is moved to the edge-aligning position 76a
in the case of the first sheet (Step 506), and the program proceeds to
Step 507. At Step 507, the program waits until a paper-discharging signal
arrives. If a paper-discharging signal arrives, the program proceeds to
Step 508. At Step 508, the aligning bar 26 is moved to the waiting
position 26b. Subsequently, a conveying operation for conveying the sheet
within the bin B is performed (Step 509). After the completion of the
conveying operation, the program proceeds to Step 510. At Step 510, it is
determined whether or not a bin-shifting signal from the main body of the
copier is present. The bins B are shifted only when a bin-shifting signal
is present (Step 511). After moving the aligning bar 26 to the
edge-aligning position 26a in order to align the sheet (Step 512), the
program returns to the main routine.
Next, the conveying operation will be explained with reference to FIG. 23.
In the conveying operation, when the sorter 1 receives a sheet from the
main body of the copier, if the sheet conveying speed of the sorter I is
slower than the sheet discharging speed of the main body of the copier,
the sheet forms a loop between the sorter 1 and the copier, causing paper
jamming. If the sheet conveying speed of the sorter 1 is faster than the
sheet discharging speed of the main body of the copier, the sheet is
pulled, providing a possibility of generating a strange sound or damaging
the sheet. Accordingly, the conveying speed of the sorter 1 is
synchronized with the process speed of the main body of the copier (Step
601). Subsequently, it is determined whether or not the flapper solenoid
122 is turned on, that is, which of the discharging outlet 16 for sorting
and the discharging outlet 15 for nonsorting is selected (Step 602). If
the flapper solenoid 122 is turned on, the discharging outlet 15 for
nonsorting is selected. Hence, the program proceeds to Step 603, where the
nonsorting-path sensor S1 performs detection. If the flapper solenoid 122
is turned off, the discharging outlet 16 for sorting is selected. Hence,
the program proceeds to Step 604, where the sorting-path sensor S2
performs detection. At Steps 603 and 604, it is awaited until the
nonsorting-path sensor S1 and the sorting-path sensor S2 are turned on,
respectively, and the program proceeds to Step 605 after the sensors have
been turned on. At Step 605, a counter for measuring a point to control
the conveying motor 117 during paper-discharging is set. Subsequently, it
is determined whether or not the counter set at Step 605 has completed its
count (Step 606). If the result of the determination is affirmative, the
program proceeds to Step 609. If the result of the determination is
negative, the program proceeds to Step 607. At Step 607, it is determined
whether or not a paper-discharging signal from the main body of the copier
is present. A sheet is deemed to have passed through the main body of the
copier only when a paper-discharging signal is absent, and, in that case,
the conveying speed is maximized (Step 608). Step 609 starts after it has
been determined at Step 606 that the current point is the point to control
the conveying motor 117 during paper-discharging, and controls the
conveying motor 117 to the paper-discharging speed of the main body of the
copier. Subsequently, a counter for measuring a point where paper
discharging is completed is set (Step 610). If the counter has counted up,
the operation is terminated (Step 611).
Next, the stapling operation will be explained with reference to FIG. 24.
First, at Step 701, the stapler swinging motor 119 is turned on in order to
move the stapler 67. The stapler swinging motor 119 is driven until both
the stapler-operating-position sensor S7 and the stapler positioning
sensor S6 are turned on, that is, until the stapler 67 moves to the
operating position 67a. Subsequently, stapling is performed by driving the
stapler motor 71. Stapling is performed after confirming that the stapler
cam sensor S10 has been turned off until the stapler cam sensor S10 is
turned on, that is, one stapling operation is completed by turning off the
stapler motor 71 after performing one revolution (Step 702). Subsequently,
the stapler swinging motor 119 is driven from the time period when the
stapler-operating-position sensor S7 is turned off to the time period when
the stapler positioning sensor S6 is turned on, that is, until the stapler
67 moves to the retracted position 67b (Step 703). Subsequently, it is
determined whether or not stapling of sheets in all the bins B has been
completed (Step 704 ). If the result of the determination is negative, the
bin unit 2 is shifted by an amount of one bin (Step 705), and the program
proceeds to Step 701 in order to perform the next stapling operation. If
the result of the determination is affirmative, the stapling operation is
terminated.
Next, the shifting operation in the sorting mode will be explained with
reference to FIG. 25.
In the shifting operation in the sorting mode, first, in order to provide
synchronization with the sheet P, a paper-discharging signal from the
image forming apparatus is monitored (Step 801). If a paper-discharging
signal arrives, a timing between the time period when the front end of the
sheet P enters the bin B, and the end of the parallel portion of the lead
cam 43 is arranged. More specifically, a counter for synchronization is
set (Step 803), and when the counter has counted up (Step 805), the
program proceeds to Step 807.
At Step 807, it is detemined whether or not the transfer paper is the final
sheet of the original. If the result of the determination is affirmative,
since it is unnecessary to further advance the lead cam 43, the revolution
of the lead cam 43 is stopped (Step 809).
If the result of the determination is negative, the program proceeds to
Step 811, where the speed of the lead cam 43 is changed. The speed of the
lead cam 43 at that time can be obtained by dividing the parallel portion
of the lead cam 43 by a time represented by (paper length.div.conveying
speed). Data on the paper length is transmitted from the main body via
serial communication shown in FIG. 17.
Subsequently, the program proceeds to Step 813, where, in order to
recognize the rear end of the sheet P, it waits until the sorting-path
sensor S2 is turned on, and then waits until the sorting-path sensor S2 is
turned off (Step 815). Subsequently, after detecting the rear end of the
sheet P by the turning-off of the sorting-path sensor S2, a counter for
counting until the sheet P is received within the bins B is set (Step
817). If the counter has counted up (Step 819), the program proceeds to
Step 821.
At Step 821, the shift speed is changed in accordance with a time interval
between paper. The shift speed is obtained by (a moving amount of the
nonparallel portion).div.(a time interval between paper) . This time
interval between paper is transmitted from the main body of the copier via
serial communication. After determining the shift speed, the program
returns to Step 801 in order to process the next sheet P.
Next, speed control of the shift motor 45 will be explained with reference
to FIG. 26.
The control of the shift motor 45 is performed using a timer interruption
function and a clock-signal interruption function of the CPU 111.
The timer interruption function is a function of generating an interruption
with an arbitrary interval by a counter within the CPU 111. The clock
signal interruption function is a function of generating an interruption
by an edge of an external pulse. In the present control, the clock-signal
sensor S13 provided in an encoder of the shift motor 45 is used in
clock-signal interruption.
The control method comprises setting an interval of timer interruption to a
time period of clock-signal interruption when the shift motor 45 reaches a
target speed, providing an addition/subtraction counter for counting this
ideal time period and clock-signal interruptions, and controlling so that
the count value of the addition/subtraction counter becomes 0. Thus, an
ideal speed is obtained.
FIGS. 26(a) and 26(b) are specific flowcharts of the above-described
control.
FIG. 26(a) shows clock-signal interruption processing. A count value of a
shift control counter, serving as the addition/subtraction counter, is
incremented. The shift control counter is provided within the RAM 113.
FIG. 26(b) shows timer interruption processing. In FIG. 26(b), first, a
count value of the shift control counter is decremented (Step 951).
Subsequently, it is determined whether the shift motor 45 is to be turned
on or off. That is, it is determined whether or not the value of the shift
control counter is greater than 0 (Step 953). If the result of the
determination is affirmative, the shift motor 45 is turned off since it is
too fast (Step 955). If the result of the determination is negative, it is
determined whether or not the value is smaller than 0 at Step 957.
If the result of the determination is negative, the value of the shift
control counter is 0, which indicates that the current speed equals the
target speed. Hence, timer interruption is terminated. If the result of
the determination is affirmative, the current speed is slower than the
target speed. Hence, the shift motor 45 is turned on (Step 959), and timer
interruption is terminated. As described above, the speed control of the
motor 45 for moving the bin unit 2 up and down and expanding the bins B is
performed.
Next, the operation of the aligning bar 26 will be explained with reference
to FIGS. 33(a) and 33(b).
When moving the aligning bar 26 to the edge-aligning position, it is
determined whether or not the current process is taking place during
stapling. If the result of the determination is affirmative, the program
proceeds to Step 1002, where the aligning bar 26 is moved to the
edge-aligning position during stapling. If the result of the determination
is negative, the program proceeds to Step 1003, where the aligning bar 26
is moved to the edge-aligning position during paper discharge.
During stapling, since sheet alignment is performed in order to push
against the paper bundle once aligned at paper discharge, it is only
necessary to move the aligning bar 26 to the verge of the paper size. In
paper discharge, however, it is necessary to push the aligning bar 26 to
varying depths in order to obtain stable alignment. Respective aligning
positions are set under such conditions, and are controlled to exact
positions by a stepping motor 303 for alignment.
When moving the aligning bar 26 to the waiting position, at Step 1101, it
is determined whether or not the current process is during stapling. If
the result of the determination is affirmative, the program proceeds to
Step 1102, where the aligning bar 26 is moved to the edge-aligning
position during stapling. If the result of the determination is negative,
the program proceeds to Step 1103, where the aligning bar 26 is moved to
the edge-aligning position during paper discharge.
During paper discharge, the sheet P is separated from the aligning
reference wall 23 during discharge. Hence, if it is intended to make the
aligning bar 26 wait at a position not interfering with the sheet P, the
aligning bar 26 must be greatly retracted. During stapling, however, since
the sheets P are in a state of contacting the aligning reference wall 23
after being once aligned, the aligning bar 26 need not be greatly
retracted. Hence, the moving amount of the aligning bar 26 is reduced in
order to speed up aligning process. The aligning bar 26 for aligning the
sheets P is controlled in the above-described manner.
Although, in the above-described embodiment, disturbance in stapling
positions by the stapler 67 is prevented by making the pushing force of
the aligning bar 26 while the stapling unit operates smaller than the
pushing force of the aligning bar 26 while the sheet P is aligned, the
same effect may be obtained, for example, by pushing the aligning bar 26
against the end portion of the sheet only while the stapler 67 moves from
the retracted position 67X to the sheet stapling position 67Y when the
stapling unit enters the sheet region, and by retracting the aligning bar
26 from the end portion of the sheet immediately before the stapler 67
operates during stapling.
In the present embodiment, if the door 96 near the stapler 67 is opened
when the reflection-type staple sensor 93 within the stapler 67 has
detected absence of staples, the stapler 67 is moved to the sheet stapling
position 67Y. At that time, the interlocking arm 91 is released by the
actuator plate 92, and the staple cartridge 69 can be detached. However,
it is also possible to electrically operate the interlocking arm 91 by the
drive of a solenoid means, a motor or the like.
Alternatively, a magnetic substance may be disposed near the staple
cartridge 69, which may be held by a magnetic force of an electromagnet
disposed near the staple cartridge 69, and locking of the staple cartridge
69 may be released by disconnecting current supply for the electromagnet
in accordance with a staple-absent signal.
In the above-described embodiment, an explanation has been provided of the
configuration wherein the paper-discharged bin and the lower adjacent bin
are open. However, the same effect may be obtained if, for example, as
shown in FIG. 34(a), in a sorter wherein only the position of the
paper-discharged bin is opened, alignment of the sheets P is completed
before the upper bin Ba completes its descent. As shown in FIG. 34(b),
when the opened amount of the paper-discharged bin Bb and the upper
adjacent bin Ba is large, alignment of the sheet P may be performed after
the completion of a shifting-up movement.
That is, it is possible to increase the number of sheets P which can be
mounted and aligned within the bin, and accuracy of alignment by adopting
the configuration wherein alignment of the sheets P is performed when the
bin is greatly opened so that the sheets P mounted on the bin are not
disturbed by a high-speed force due to the alignment.
In FIG. 34(b), a relationship of l2>l1 and l3>l1 is satisfied, where l1
represents a normal interval between bins, l2 represents an interval
between the upper adjacent bin Ba of the paper-discharged bin Bb and the
upper adjacent bin of the bin Ba, and l3 represents an interval between
the paper-discharged bin Bb and the lower adjacent bin Bc of the bin Bb.
While the present invention has been described with respect to what is
presently considered to be the preferred embodiments, it is to be
understood that the invention is not limited to the disclosed embodiments.
The present invention is intended to cover various modifications and
equivalent arrangements included within the spirit and scope of the
appended claims.
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